Animating a bomb that explodes at a certain keyframe after cell fracture
Okay, so what I've figured out is that after creating my group, I had to set up the animated "Dynamic" box for when I wanted it inactive and when I wanted it active again.  After all animation had been set up, I hit ctrl+L > Animation Data and that did the trick!  Now the explosion takes place at the frame I wanted.  

The key is to set all of the animations for the active member of the group BEFORE making the link to the Animation Data!  

Maybe this will help others as well!